1. Field of the Invention
The present invention relates to an apparatus and a method for combining an optical waveguide and optical fibers, and more particularly, to an apparatus for combining manually aligned optical fibers with an input and output optical waveguide of an integrated optical device manufactured by integrating an optical waveguide device having various functions with a substrate and a method therefor.
2. Description of the Related Art
In general, there are two methods for attaching optical fibers to an optical waveguide device. In a method referred to as an active alignment method, input light is guided to optical fibers or an element, the position of the optical fibers is precisely controlled, optical power in an optical waveguide or in an output waveguide of the optical fibers is measured, and the optical fibers and the optical waveguide are fixed in a state in which the combination of the optical fibers with the optical waveguide maximizes light transmission. In a passive alignment method, precise alignment of the optical fibers and the optical waveguide is automatically performed by the shape and structure of the combined portion, without guiding light when the optical fibers are combined with the optical waveguide.
The active alignment method is practical for combining the optical fibers with the optical waveguide. In the active alignment method, a light source and a photodetector are required for aligning the optical fibers and the optical waveguide. It is difficult and takes a long time to align the optical fibers and the optical waveguide, since the alignment must be performed with respect to an alignment axis having six degrees of freedom (it must be rotated with respect to three straight axes perpendicular to each other and three straight axes) with submicron precision.